天然烧变高岭石中水铝英石的发现

THE EXISTENCE OF ALLOPHANE HEATED METAKAOLINIE

作者用DTA、TG、XRD、29Si和27AlMASNMR等手段对我国北方的一些天然烧变高岭石及其热处理产物进行了研究．首次在天然烧变高岭石的29Si魔角旋转核磁共振谱中（MASNMR）记录到了-79．0×10－6位置附近的水铝英石的特征29Si信号，说明在一定的自然条件下，经过水的化学作用，变高岭石可以转变成水铝英石。但是，水铝英石是一种非晶质相物质，它不稳定，易脱失结构水而转变成其它物相。

Three naturally heated metakaolinite samples have been examined using DTA, TG, XRD and MAS NMR methods. In the 29 Si MAS NMR spectra, the weak 29 Si signal of allophane near - 79.0 × 10 6 was recorded. It is could be concluded that allphane does exist in the samples of nat-urally heated metakaolinite, but, it is present in a little amount. It is very unstable and can be eas-ily transformed into other phases. Its discovery is very important to the kaolinite phase-transfor-mation theory.